The Warming and Propagating Features of the Equatorial Pacific Surface Temperature During El Nino Events

In this paper, firstly the features of long variation of the Equatorial Pacific Sea Surface Temperature (EPSST) are probed by use of the spectrum analysis of the principal component of time coefficients from standared EOF. Then the warming and propagating features of EPSST during El Nino events are studied by using the CEOF method. The results show El Nino events have three patterns in the light of their spatial warming range: (1) warming in the central and east Pacific; (2) warming in the whole equatorial Pacific; (3) warming only in the east Pacific. Furthermore, they could also be divided into other three patterns based on the propagating features of EPSST during their development: (1) warming first in the east Pacific, then propagating westward; (2) warming occurring in the east and west Pacific simultaneously, then propagation towards the central Pacific; (3) warming first in the west Pacific, then propagating eastward.